Reality Is Not What It Seems – The Journey To Quantum Gravity – Carlo Rovelli

I was hoping I could write this post during the quiet early morning where I could be at peace and really think. But life has been too busy recently and I wanted to get this written.

I saw this book mentioned somewhere and is one of the few I’ve immediately ordered based on a review. The title “Reality Is Not What It Seems” stood out to me and I liked that it is from an angle I’ve always been afraid to approach given the limitations of my own IQ. Physics and college level science in general are subjects from which I’ve always quickly run away. I remember at OSU I spent one hour in a physics/calculus something or other course for science majors which was enough to make me high tail it back to the business school math and overall curriculum. This book promised to give me “a lucid overview of quantum gravity, the field of research that explores the quantum nature of space and time, seeking to unify quantum mechanics and general relativity.” I was looking for a similar explanation in the way Carl Sagan brought a lot of difficult to understand science to the masses with Cosmos. I wanted to understand a scientific explanation for the reality which surrounds us.

For the past decade or so I’ve read, researched, pondered and generally thought very deeply about the nature of reality, where we are, where we come from and a general, ‘someone please tell me what all this is,’ sort of mindset. This isn’t a subject that is easily discussed with others and those that do already have their opinions formed, most of which are religious ones they grew up with. It is enough to make one feel very alone since 95% of the people on this planet will use religion as their explanation.

So I find it very refreshing to find a book that uses the frontiers of very complex science and explain it in a way I can understand. I really like how he confirms that we might all be wrong but that science is the best method for trying to piece the truth together.

This is timely advice as I feel the masses have been pushing back against science and reason in favor of faith and superstition! This is very hard for me to believe since more of humanity has access to education than ever before in the entire history of our species. I could be wrong in my assessment, but I think Carl Sagan really pushed science forward by explaining complex scientific discoveries in a way regular people could understand; and I think that the mainstream was receptive. But this initial, positive reception began to quickly waiver and decline. There were ups and downs over the past three decades but now with the election of Trump I feel that science has just taken a big blow to the head with ignorant opinions ‘trumping’ scientific facts. It is the big regression, and if describing it as a “dark age” seems a bit dramatic then let’s go with a general dimming of the mainstream intellect. With the advances in technology there is just too much information to process; better to go with the guy explains things simply, loudly and that already conform to your own beliefs and opinions.

Regardless of what the ‘mainstream’ thinks we’re all on our own individual journey and individually all must decide what to believe for ourselves. For me, I know there is much we do not understand, but science is the best way to confirm what little we do. Mr. Rovelli shares this thinking which are illustrated by some of the following quotes.

So let’s get to my favorite quotes:

The closure of the ancient schools such as those of Athens and Alexandria, and the destruction of all the texts not in accordance with Christian ideas was vast and systematic, at the time of the brutal antipagan repression following the edicts of Emperor Theodosius, which in 390-391 declared that Christianity was to be the only and obligatory religion of the empire.

There is a deep acceptance of life which were an integral part:Do you not see that nature is clamoring for two things only, a body free from pain, a mind released from worry and fear for the enjoyment of pleasurable sensations?And there is a serene acceptance of the inevitability of death, which cancels every evil, and about which there is nothing to fear. For Lucretius, religion is ignorance: reason is the torch that enlightens.

The Catholic Church attempted to stop Lucretius: in the Florentine Synod of December 1516, the Council of Trent banned his work. But it was too late. An entire vision of the world that had been swept away by Christian fundamentalism was re-emerging in a Europe that had reopened its eyes.

There is none of this in the world of Democritus as sung by Lucretius. There is no fear of the gods; no ends or purposes in the world; no cosmic hierarchy; no distinction between Earth and heavens. There is a deep love of nature, a serene immersion within it; a recognition that we are profoundly part of it; that men, women, animals, plants, and clouds are organic threads of a marvelous whole, without hierarchies. There is a feeling of deep universalism, in the wake of the splendid words of Democritus: “To a wise man, the whole earth is open, because the true country of a virtuous soul is the entire universe.”

Ptolemy was an astronomer who lived in Alexandria in the first century of our era, under the Roman Empire, when science was already in decline and about to disappear altogether, overwhelmed by the collapse of the Hellenistic world and suffocated by the Christianization of the empire.

After the collapse of ancient science, no one throughout the Mediterranean was capable of understanding Ptolemy – or any of the other small number of major scientific works that survived the catastrophe, such as the Elements of Euclid. In India, where Greek learning had arrived thanks to rich commercial and cultural exchanges, these books were studied and understood.From India, this knowledge returned to the West, thanks to learned Persian and Arab scientists who were able to understand an preserve it.

It is easy to understand things once someone has thought them through. The difficulty lies in thinking them through in the first place.

Perhaps, it is no longer a good idea to trust your intuitions after thirty….

His physics has the pristine clarity of a song. For him, the world is not made of things; it’s constituted of an abstract mathematical structure that shows us how things appear, and how they behave when manifesting themselves.

A stone is a vibration of quanta that maintains its structure for a while, just as a marine wave maintains its identity for a while, before melting again into the sea.

We, like waves and like all objects, are a flux of events; we are processes, for a brief time monotonous….

Quantum mechanics teaches us not to think about the world in terms of “things” that are in this or that state but in terms of “processes” instead. A process is the passage from one interaction to another.

Richard Feynman, who more than anyone has known how to juggle with the theory, has written: “I think I can state that nobody really understands quantum mechanics.”

There is a curved spacetime born fourteen billion years ago, nobody knows how, and still expanding. This space is a real object, a physical field with its dynamics described by Einstein’s equations. Space bends and curves under the weight of matter and plunges into black holes when matter is too concentrated.Matter is distributed in a hundred billion galaxies, each containing a hundred billion stars, and is made up of quantum fields that manifest themselves in the form of particles, such as electrons and photos, or as waves, such as the electromagnetic ones that bring us television images and the light of the sun and stars. These quantum fields make up atoms, light, and the full contents of the universe. They are strange objects: their quanta are particles that appear when they interact with something else; left alone, they unfurl into a “cloud of probability.” The world is a swarm of elementary events, immersed in teh sea of a vast dynamic space that sways like the water of an ocean.
With this image fo the world, and the few equations that make it concrete, we can describe almost everything that we see.
Almost. Something is missing. And it is this something that we are seeking.

Archimedes rebels against the form of knowledge that insists on there being mysteries that are intrinsically inaccessible to human thought.

The point at stake here is not the presumption of knowing everything. it is the opposite: an awareness that yesterday’s ignorance may have light shed on it today; and that today’s might be illuminated tomorrow.

Quantum mechanics can be understood as the discovery that information in nature is always finite.
In fact, the entire structure of quantum mechanics can be read and understood in terms of information, as follows. A physical system manifests itself only in interacting with another. The description of a physical system, then , is always given in relation to another physical system, the one with which it interacts. Any description of a system is therefore always a description of the information a system has about another system, that is to say, the correlation between the two systems.

“everything is information.”

Whenever you consider a phenomenon certifying the passage of time, it is through the production of heat that it does so. There is no preferred direction of time without heat.

The difficulty of grasping this idea comes from the fact that it is hard for us to think of a world without time, and of time emerging in an approximate manner. We are too used to thinking of reality as existing in time. We are beings who live in time: we dwell in time, and are nourished by it. We are an effect of this temporality, produced by average values of microscopic variables. But the limitations of our intuitions should not mislead us. Understanding the world better often entails going against intuition. If this were not the case, understanding would be easy.Time is an effect of our overlooking the physical microstates of things.
Time is information we don’t have.Time is our ignorance.

A child begins to live on the day when a person dreams of her for the first time, long before her conception, or when she forms her first self-image, or when she breathes for the first time, or when she recognizes her name, or when we apply any number of other conventions: they are all useful but arbitrary. They are ways to think, and to orient ourselves whthin the complexity of reality.

The finalistic aspects of the biological world (this is Darwin’s momentous discovery) are therefore a result of the selection of complex forms effective in persisting. But the effective way of continuing to exist in a changing environment is to better manage correlations with the external world, that is to say, information: to collect, store, transmit, and elaborate information. For this reason, DNA exists, together with immune systems, sense organs, nervous systems, complex brains, languages, books, the library of Alexandria, computers and Wikipedia: they maximize the efficiency of information management. The management of correlations favoring survival.

The nature of man is not his internal structure but the network of personal, familial, and social interactions within which he exists. It is these that “make” us, these that guard us. As humans, we are that which others know of us, that which we know of ourselves, and that which others know about our knowledge. We are complex nodes in a rich web of reciprocal information.

The truth is in the depths. – Democritus

Only by keeping in mind that our beliefs may turn out to be wrong is it possible to free ourselves from wrong ideas, and to learn. To learn something, it is necessary to have the courage to accept that what we think we know, including our most rooted convictions, may be wrong, or at least naïve: shadows on the walls of Plato’s cave.Science is born from this act of humility: not trusting blindly in our past knowledge and our intuition. Not believing in what everyone says. Not having absolute faith in the accumulated knowledge of our fathers and grandfathers. We learn nothing if we think that we already know the essentials, if we assume that they were written in a book or known by the elders of the tribe. The centuries in which people had faith in what they believed were the centuries in which little new was learned.

The nature of scientific thinking is critical, rebellious, and dissatisfied with a priori conceptions, reverence, and sacred or untouchable truth. The search for knowledge is not nourished by certainty: it is nourished by a radical distrust in certainty. This means not giving credence to those who say they are in possession of the truth. For this reason, science and religion frequently find themselves on a collision course. Not because science pretends to know ultimate answers, but precisely for the opposite reason: because the scientific spirit distrusts whoever claims to be the one having ultimate answers or privileged access to Truth. This distrust is found to be disturbing in some religious quarters. It is not science that is disturbed by religion: there are certain religions that are disturbed by scientific thinking.To accept the substantial uncertainty of our knowledge is to accept living immersed in ignorance, and therefore in mystery. To live with questions to which we do not know the answers. Perhaps we don’t know them yet, or who knows, we never will.To live with uncertainty may be difficult. There are those who prefer any certainty, even if unfounded, to the uncertainty that comes from recognizing our own limits. There are some who prefer to believe in a story just because it was believed by the tribe’s ancestors, rather than bravely accept uncertainty.Ignorance can be scary. Out of fear, we can tell ourselves calming stories: up there beyond the stars there is an enchanted garden, with a gentle father who will welcome us into his arms. It doesn’t matter if this is true – it is reassuring.There is always, in this world, someone who pretends to tell us the ultimate answers. The world if full of people who say that they have The Truth. Because they have got it from the fathers; they have read it in a Great Book; they have received it directly from a god; they have found it in the depths of themselves. There is always someone who has the presumption to be the depository of Truth, neglecting to notice that the world is full of other depositories of Truth, each one with his own real Truth, different from that of the others. There is always some prophet dressed in white, uttering the words: “Follow me, I am the true way.”